$_SERVER['SERVER_PORT'] server port passed as string

[LocalHeroPro]

On that line: https://github.com/slimphp/Slim-Psr7/blob/master/src/Uri.php#L301 I got error, because value passed is string "443".
Can we cast string to int and after that check if it is good for us value?
Value is passed starlight from $_SERVER['SERVER_PORT']
PHP Fatal error: Uncaught InvalidArgumentException: Uri port must be null or an integer between 1 and 65535 (inclusive) in vendor/slim/psr7/src/Uri.php:306